Power steering mechanism



Dec'. 5, 1939.

R. TINKER POWER STEERING MECHANI SM Filed Jan. l2, 1959 3 Sheets- $11661l 1 WITNESSES ATTORNEYS 7 Dec., 5, 1939. R, TlNKER 2,182,102

POWER STEERING MECHANISM Filed Jan. 12, 1959 3 Sheets-Sheet 2 m A a fil.- ,w

VMVMVVVVVVVVVVVM WITN ESSES Fied Jan. 12, 1939 s sheets-sheet s INVENTOR* Ralph T11/2719924 wrruesst's arl/amg ATTORNEYS Patented Dee. 5, i939 N UNITED vsrlii'rras PATENT oI-r-lcA v 4 Claims. This invention relates to an improved power steering mechanism adapted to be used on tractors or other similar vehicles, an object being to provide an improved construction whereby the vehicles are articulated centrally and one section r part is swung in respectv to the other section or part when steering.

Another object 'of the invention' is to provide a steering mechanism for a vehicle that is articulated substantially centrally wherein the parts are so `formed .that 'two steering wheels may be used and the driver face in either direction and operate the respective steering wheels to readily `steer the vehicle in the same way when using either steering wheel.

A further object of the invention is to provide a steering mechanism and associated parts for a vehicle articulated-centrally wherein the 'operator-s platform adfpart of the mechanism are supportedy above the articulated connection be-, tween the parts of the vehicle. i *ai In the accompanying drawings- Fig. 1 is a longitudinal vertical sectional view through'Fig. 2 approximately on the line II;

Fig. 2 is a top plan view of a vehicle with a steering wheel embodying the inventionapplied thereto, certain parts being broken away for better illustrating the detail construction;

Fig. 3 is a sectional view through Fig. 1 approximately on the line 3-3.

Referring to the `accompanying drawings by numerals, I indicates an operator's platform 'which is supported on vthe front frame 2, as hereinafter. fully described. The frame 2 is. prof; vided with a yoke 3 which'coacts with a yoke 4 extending forwardly from the rear frame 5, as

shown particular ly in Fig. 1. As the vehicle may be driven with equal facility in either direction, either end might-,be called the front but forv the purpose of this descriptionl the frame 2 willbe considered the front frame as it carries or supports an engine 6 of any desired kind.

The front frame is supported by suitable trac-v tion wheels 'I while the rear'frame is supported by suitable traction wheels 8. The driving shaft 9 is rotatably mounted in frame 2 while the coacting driving shaft Ill is rotatably mounted in the frame 5, said shafts being connected by a universal joint II. 'I'he shaft-I0 is connected to suitable gearing I2 and other transmission devices for rotating the rear wheels 8, as fully disclosed in my Patent No. 2,150,011, issued March '1, 1939, and in my co-pending application Serial No. 208,575, led May 18, 1938, and, therefore, no additional description is thought to be necessary'.

The same is true in regard to the bevel 4gears I3 and associated parts which drive the front wheels 'I. When power is appliedto the shaft 9, both shaftsv 9 and I0 will rotate 'in the same direction and, consequently, both the front and rear wheels 5 will rotate for propelling the vehicle in the desired direction. When the shafts B'and I0 rotate in one direction the vehicle travels in a given direction and when these shafts are reversed the vehicle travels in the opposite direction. Means, lo as ,hereafter fully described, have been provided for .swinging frame 2 in respect to frame 5 for steering purposes through the application of power from the engine 6. Also powerfrom the engine 6 is transmitted to shafts 9 and I0 and 15 associated parts for rotating the respective traction wheels.

As shown particularly in Fig. 1, the crank shaft of the engine is provided with an vextension 6' and this extension is connected to the 'shaft I4 20 Aby any desired form of clutch I5. When the clutch I5 is functioning shaft I4 is continually rotated and continually rotates the pulley wheel I6 and the bevel friction'gear I'I. A depending arm I8 is pivotally mounted at I9 on the plat- 25 form I and extends downwardly so as to engage the pins on the sliding clutch section I5',

whereby when the arm I8 is swung in one direction the clutch I5 will be engaged and when swung in the opposite direction the clutch I5 will 30 be disengaged. It will be understood that the clutch section I5 is splined to shaft I4 and by this arrangement the shafts 6 and I4 .are connected and disconnected. A link or rod 2| pivotally connected with the arm I8 through shaft 35 I8 and arm I8" extends almost the full length of the platform I, whereby at its opposite end it is pivotally connected at 22 to afoot lever 23,l which foot lever ispivotally mounted at 24 on a bracket 25 bolted or otherwise rigidly secured to 40 the bottom of platform I. A second foot lever 26 is pivotally mounted at 21 on a suitable bracket carried bythe platform I. The lower end of the foot-lever 26 is pivotally connected with the link or rod 2I. Y 45 When the foot lever 26 is forced toward the engine 6, rod 2| is pulled 'to the right, as shown in Fig. ,1, and the clutch I5 is disengaged. When lever 23\is pushed in a direction away from the motor 6, the same action takes place. The clutch I5 may be of any desired form of clutch, as for instance the kind having a spring, such as spring 28, for forcing the same into functioning position when both of the foot levers'have been released. These 001; levers are arranged as shown par- 55 ticularly in Fig. 1 in order to coact with the front and rear steering wheels 29 and 39. The seat 3| is carried by a suitable post 32 and is rotatable so that theoperator may faceieither of the wheels 29 or 39 and, consequently, may put his foot on either of the foot pedals or levers 23 or 26. Y

A gear housing 33 forms part of the front frame 2, as shown in Fig. 2, and extends upwardly to the platform I. The shaft I4 extends through this housing and has clutch members v34 and35 freely rotatably mounted thereonbetween suitably placed collars xed on shaft I4. A clutch member 36 splined on shaft I4 isI arranged between clutch members 34 and 35 and is adapted to be interlocked with eitherA clutch member ac-` cording to which direction it is desired to drive the shafts 9 and I0. An auxiliary shaft I4' is carried by the gear housing 33 and has adjacent one end a gear wheel 3l and adjacent the other. end a sprocket wheel 38. A chain passes over the sprocket wheel 33 and a sprocket wheel 39 carried by the clutch member 34. A pinion 40 is secured to clutch member 35 and is continually in mesh with the gear wheel 31. A` second pinion 4I rigidly secured to shaft I4' is in continuous mesh with a large gear wheel 42 which is rigidly,

secured to shaft 9. lWhen it., is desired to drive shaft 9 in one direction the splined clutch member 36 is moved into engagement with .the clutch member 34 and when it is desired to reverse the rotation of shaft 9 the'splined clutch member 36 is moved into engagement with clutch member 35. An arm t3 is pivotally mounted at 44 from platform I and is operatively connected with the splined clutchmember 36 to slide this clutch member back and forth as desired. A link or rod 45 pivotally connected with the arm 43 through shaft t3' and arm .53", extends rearwardly to a position opposite the seat 3i where it is pivotally connected to the lower end of a hand lever t6. The hand lever t6 isv pivotally mounted at 'l on a suitable bracket carried by platformv I. A second hand lever 38 lis arranged in line with the hand lever e6 and is pivotally mounted at 91 so that the lower end may be pivotally connected with a link 69 which extends forwardly and' is pivotally connected at 59 to a bell crank lever 5i, which bell crank lever is pivotally mounted on a suitable shaft 52 carried by suitable brackets vsecured to the platform I. The bell crank lever 5I is pivotally connected with' a link 53 which is bifurcated at its lower end and the bifurcated part pivotally connected with a sleeve 54 slidingly mounted on-shaft 55. -This shaft is pivotally mounted at 56 on a standard 57 and carries at the forward end a pulley 53 for accommodating a belt 59. I Also a friction wheel 60 is connected to shaft 55 and when lowered frictionally engages tion, Serial'- No. 208,575 and, therefore,`wi1l not be claimed in the present application, nor be fur.- ther described except to state that the shaft 55 is adapted to operate thel worm 6I and 'thereby actuate certain mechanism to be connected to the vehicle atl the rear, as for instance a-cultivator. It will be seen, therefore, thatl lever 49 controls the direction of rotation oitheshaft 55 and by correctly positioning the samefthe shaft may be.

f' 'maintained stationary. Lever l46, however, controls the position of the ,splined clutch member 36..l` Ii' desired, a suitable pawl-and-rack 62 could 'be providedfor each of the levers' 46 and 46 to cured to the 'shaft 43'. The depending arms I9 and 43 are arranged centrally of the vehicle so -as to depend directly .on the clutch I5 and the splined clutch member 36,1while the rods 2| and `45 are at one side as clearly shown in Fig; 2. From Fig. 2 it will also be seen that the operator while seated on the lseat 3| may operate levers 46 .and 49 when facing either direction and when facing in one direction operate pedal 23 and wheel 39, while the wheel 29 and pedal 26 may be readily operated when facing in the opposite direction.

As shown in Fig. l, the frames 2 -and 5 are articulated or pivotally connected together by the use of yokes 3 and 4 held in place by' aligned pins S3 and 64. The yoke 4 at the upper partis provided with an extension 55 which, as shown in Fig. 2,`is providedwith an arc-shaped rack 66 end at each end of the rack there is provided an outwardly extending tooth 6l so as to prevent movement of the pinion 66 beyond the end of the rack. As the rack 66 with the extension 65 is swung by the pinion sa, the frames z and. s wm be moyed at an angle to each other and this angular relation will cause the vehicle to travel around a curve or in any desired direction as required' by the operator seated on the platform I.

The friction gear I1, rack 66 and parts therebetween coact to transmit power to yoke' so as to produce a desired angular relation between the frames to secure the desired steering action. The shifting of the frames in respect to each other around the axes of the pivot pins 63 and 64 is usually carried out while shafts 9 and I 9 are rotating.

From Figs. 1 and 2 it will be seen that vpinion 39 is rigidly secured to a vertically extending shaft 69 mounted in suitable bearings to the platform I and on the top side of the supporting yoke 10. This supporting yoke', as shown in Fig. 3, is a flattened U-shaped structure with the bottom section 'I0'. bolted or otherwise rigidly secured to the enlargement 1I of the front frame 2. The bottom section 10' merges into upwardly extending sections 10 and 19"', which are bolted or otherwise rigidly secured at their upper ends to the platform I. The supporting yoke 'i0 is comparatively wide, as shown in Fig. 1, and supports shafts 'I4 and 69 and a number of other parts, as illustrated imFlga 1 and 3.

Referring again to the shaft 69, not only is the pinion 69 rigidly secured thereto but also the vwormwheel 12 which continually meshes with the worm 13. Worm i3 is rigidly secured to shaft I4 journaled in suitable bearing brackets 'l5 and 16, as shown in Fig. 3. v0n vshaft 14, centrally thereof, ismounted a friction spool 11 having a central section 18 and friction gear sections 19 and 39, said gear sections facing each other. These parts are arranged so that when the structure 11 isin its central orr neutral` position the bevel friction gear' I1 will be spaced midway between the friction gears 'i9 and 80, as illustrated in F18. 3.v The friction spool 11 is splined to shaft 14 so that whenever the friction gear I1 is out of contact therewith, wheel 12 and associated parts, including the extension 65, will remain stationary. It is only necessary to shift the friction. spool 11 one Way or the other toengage the friction gear I1. It will be understood that as long as clutch I is functioning and the engine is operated, the bevel friction gear I1 will be rotated.

The friction spool'11 at one end is provided with a hub 8| and at the other end with a hub 82. These hubs are provided .with suitable grooves, as shown in Fig. 2, andvin each groove there is a slip ring 83 having suitable pins 84.

, The pins 84 ofA hub 8| are rotatably mounted in the bifurcatedv end 85 of a lever 86, which lever A link 89 is pivot` ispivotally mounted at 81. ally connected at 98 to the Outer end of lever v86. This link is also pivotally'connected at 8| to one end of a bell crank lever 92, the opposite end being pivotally connected at 93 to a connecting link 94, which in turn is pivotally connected Arm 96 is Arigidly secured to apost 91 journaled in a suitable bearing of platform I and rigidly secured to the steering wheel '38. Bell cran); lever 92 is rigidly secured to a post or stem 98 which is rigidly secured to the steering wheel 29. Post 98 is rotatably' mounted in a suitable bearing 89 Acarried by the platform I. I'his general arrangement is shown in. Fig. 2 and by reason of the diagonal position of the link 94, the steering wheels operate in unisonv but permit the usual turning of the respective steering wheels when facing inv either direction.

When the operator is facing to the rear, as shown in. Fig. 2, the rotation of steering Wheel 38'clockwise will turn the vehicle to the right. If the operator were facing in the opposite direction and operating the steering wheel 29, a turning of the steering wheel clockwise would turn the vehicle to the right. When either of -the steering wheels 29 -or 38 is turnedhub 8| will be pulled or pushed, as the case may be. If the turning movement is such as friction spool 11 will be moved accordingly and one of the friction gears 19 orV with friction gear I1, but if the hub 8| is moved in the opposite direction the opposite friction gear will be engaged. ,In this way the friction spool with its shaft 14 may be rotated in either direction to anyv desired extent. This statement,

however, is limited by the fact that the extending teeth 61 will limit excessive movement in either direction-and also certain other mechanism hereinafter fully described will limit 'mover ment in either direction.

The worm gear 12 is provided with an upstand- |88 which coacts with a pin |8| rigidly secured to a slide rod' |82 carriedby suitable brackets |83 and |84, as shown in Fig. 2. A bell crank lever |85 is pivotally mounted at |86 on a suitable supportl carried by the platform I and has a bifurcated end |81 fitting into the hub 82, while the opposite end, at |88, is formed with a slot accommodating a pin extending from the slide `rod |82. end of the rack 66, pin |88 will strike -pin |8| and move the slide rod |82. If the pin' |88 is moving clockwise, 'as shown in Fig-2', the result will bethat the hub 82 and friction spool 11 will be pulled so as to move out of engagement with the friction gear I1. If the pin |88 is moving counterclockwise the reverse action will Vtake place arid-hub 82 will be pushed for disconnecting to push hub 8|, the

88 will he engaged As the pinion 68 nears either' the-friction spool from the gear I1'. As this action is produced by power from the engine through the various mechanisms heretofore de-l'l scribed, the connection between gear |1 and the friction spool will be broken notwithstanding the action of the operator in respect to the steering Wheels 29 and 38. However, this action will not bring the frames 2 and 5 back into alignment but will merely prevent these frames from turning more than a certain angle with respect to each other. The respective frames and associated n parts of the vehicle will remain at their extreme anguar position until the operator moves either of the steering wheels to change .the angle to a straight line.

It will be noted, particularly7 from Figs. 2 and 3, that springs |89 and ||8 are positioned to surround the shaft 14 and act to center the friction spool-11 whenever permitted to do so.

While I have illustrated and described` what I believe to be a preferred embodiment of my `invention, it is obvious that various changes may be made with regard to the form and arrangement of parts without'departing from my invention, and hencev I do not limit myself to lthe pre.- cise details set forth but consider myself at liberty .to make such changes and alterations as said shaft, a power driven friction pulley positioned between the ends of said spool and normally out of engagement with the spool, a pair of spaced steering posts on the frame arranged on a longitudinal line, means operatively connecting both of said steering Aposts to the friction spool to move the same longitudinally of its shaft to have its ends engage at different times said friction pulley, said means including a link motion structure including a bell-crank lever secured rigidly to one-of said wheels, an arm secured to the other wheel, a link connecting said arm with one arm of said bell-crank lever, and means including a second link connecting the other arm of said bell-crank lever with said spool, atoothed segment fixed to one of said frames, a pinion carried by the other frame continually in mesh with said segment and means for transmitting motion from said`spool to said pinion when said friction gear is rotating said spool.

2. A power steering mechanism for a vehicle including a pair of articulated wheel supported frames, an operatorsplatform, a substantially U-shaped support for said platform having at sides extending ,at anangle to the horizontal, means for securing said U-shaped support to one of said frames, a transverse shaft supported by said fiat sides, a friction spool splined to slide onv said shaft, a power driven friction gear positioned between the ends of said spool and normally out the friction spool to move .theI same longitudinallyofsaid shaft, atoothed segment 'fixed to the other of said frames, a vertical shaft having its upper end respectively rotatably Journaled to' said platformv and its lower end journaled to the top of said Ufshaped support, a pinion secured to said vertical shaft positioned to continually mesh with said toothed segment; 'a worm wheel secured to said vertical shaft, and a worm in mesh with said worm wheel secured to the shaft on which said spool is mounted whereby said toothedv segment will be moved in either direction according to -which end of Asaid spool is engaging said friction gear. y v 1 3. A power steering mechanism for a vehicle including a pair of wheel frames pivotally connected together at their adjacent ends, onev of said frames having a toothed segment and thel other a widened section ontop, an operators platform, a substantially U-shaped frame having its center secured rigidly to said widened section and its `top secured to said platform for secured to said horizontal shaft positioned to be continually in mesh with said worm wheel, a

friction 'spool splined to yslide longitudinally on l said horizontal shaft.' a power driven.friction pinion positioned Vbetween the ends of said spool and normally out of contact'th'erewith, a pair of steering posts carried by said platform` and means for operatively connecting said posts'v with said spool for moving the spool longitudinally on said horizontal shaft and into and out of'mesh with said power driven friction gear.

. 4. In apower steering mechanism for a vehicle, a sliding friction spool, Va pair of steeringposts land means for transmittingA motion from said posts to said spool for moving the spool in either of two directions, said means including an arm rigidly secured to one -of said posts, a bell-crank lever secured to the other of said posts, a link connecting said arm with one leg ofsaid bellcrank lever, said arm ,extending from the opposite side of the first lmentioned post to the associated leg of said bell-crank lever whereby the posts rotate in unison but in opposite directions, and means including a linkl for connecting the other leg of said bell-crank lever to said friction spool.

- f RALPH TINKER. 

